Chronic Wasting Disease 
(CWD)

 

For More Information on Chronic Wasting Disease:

US Dept of Agriculture- APHIS

Nebraska Game and Parks Commission


 
 
Status in Nebraska:  
CWD has been found in western Nebraska as far east as Hall County.  The Nebraska Game and Parks Commission has been conducting voluntary tests each year on deer harvested by hunters to determine the spread of the disease.  The tests began in the western part of the state; however they are done statewide now.  To date, over 15,000 deer have been tested, however many of these deer are young deer because the process of removing the lymph nodes can destroy the deer’s cape, preventing the hunter from being able to have their trophy bucks mounted.  The younger deer are less likely to have the disease, so for the 2005 hunting season the Game and parks is going to attempt to obtain the nodes of more mature deer as well by trying to persuade the hunters to allow them to.  If the disease is detected in an area, regulations on deer hunting are loosened and hunters are allowed to help control the population to prevent further spreading of the disease.

Distribution:  
It has been found in wild deer and/or elk in Colorado, Wyoming, Nebraska, South Dakota, Wisconsin, Utah, New Mexico, Illinois, and Saskatchewan, Canada. In captive deer and or elk, it has been found in Colorado, Montana, South Dakota, Oklahoma, Kansas, Nebraska, Wisconsin, Minnesota, Saskatchewan, and Alberta.

Origin:  
It is thought to have originated in Colorado

Characteristics:  
CWD is a neurological disease that occurs mostly in deer and elk, but has recently been found in moose.  CWD belongs to the family of diseases known as transmissible spongiform encephalopathies (TSEs).  CWD is a progressive, fatal, degenerative disease. Clinical signs in affected animals include loss of body condition, behavioral changes, excessive salivation, increased drinking and urination, depression, and eventual death. CWD is always fatal. There is no known treatment, vaccine, or live animal test for CWD.

Impacts:  
The biggest impact that CWD has is that it will drastically reduce the deer and elk populations in an area.  It also causes concern among hunters in areas that it first appears because the hunters are afraid that they may catch the disease.  In Nebraska, most hunters understand that CWD can not be transmitted to humans and are not as concerned as they used to be.

Management:  
Extensive testing is being conducted in areas that are at risk for CWD.  It is diagnosed by taking samples from the Obex tissue of the brain in deer and elk, however, the lymph nodes can be used to diagnose it in deer as well.  There is no way to directly control the spread of CWD, but there are many indirect ways to control it.  The most common method is to eradicate the deer or elk from an area to wipe out the disease or stop the spreading.  Other preventative measures have been taken also.  For example in Nebraska, hunters are no longer allowed to hunt over an area where bait has been placed to attract the deer.  By doing this, hunters are discouraged from placing out salt blocks and feeders, causing the deer to congregate in one area, increasing the chances of spreading the disease.

History:  
CWD was first discovered in a deer at a research facility in Colorado in 1967, and was found a few years later in Wyoming.  It was determined to be a TSE in 1978 in Wyoming.  The first wild cases were found in Colorado and Wyoming in the early 1980’s and the first Nebraska case was discovered in Chase County, Nebraska in 2001.